what would need to happen to change a lead atom into a gold atom

Converting a lead atom into a gold atom requires manipulating the atom's core, which is a very complex process. Here's what it would take:

Changing the Protons: Elements are defined by the number of protons in their nucleus. Lead (Pb) has 82 protons, while gold (Au) has 79. To turn lead into gold, you'd need to remove 3 protons from the lead nucleus.

Overcoming Strong Forces: The strong nuclear force holds protons and neutrons together incredibly tightly.  Overcoming this force  requires a tremendous amount of energy.